Friday, August 22, 2025

Uniquely preserved artillery offers clues of European colonisation




Lund University
Recovering gun bed, Gribshunden 

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Phillip Short and Brendan Foley recover a gun bed from the wreck of Gribshunden, 2021. Image: Klas Malmberg. 

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Credit: Klas Malmberg





Lund University archaeologists have revealed details of late medieval artillery from the wreck of the royal Danish-Norwegian flagship, Gribshunden. The shipwreck is the only known example of its kind from the medieval period – as both ship and weapons are nearly identical to those of the early Spanish and Portuguese explorers. The new study tells the story of how early modern maritime adventurers were equipped to start the process of dominance and colonisation across the world.

WATCH VIDEO STORY – see artillery found on Gribshunden


“Diving on this late medieval royal shipwreck is of course exciting. However, the greatest satisfaction is when we can actually put the pieces of the puzzle together later on; combining Martin’s castle expertise with Kay’s deep understanding of artillery”, explains Brendan Foley, the marine archeologist behind the study, who worked closely with fellow LU archaeologist Martin Hansson and medieval artillery expert Kay Douglas Smith.

Gribshunden, the flagship of the Danish-Norwegian King Hans, sank mysteriously in 1495 off the coast of Ronneby, Sweden. The wreck is internationally significant as the world’s best-preserved ship from the Age of Exploration – a proxy for the vessels of Christopher Columbus and Vasco da Gama.

Ocean-going ships like Gribshunden and the artillery they carried were critical technologies for European explorers after 1492. The voyages to America and into the Indian Ocean via the Cape of Good Hope led to European colonization around the world. Gribshunden is a rare archaeological resource, as it is the most complete example yet discovered of a late medieval carvel warship. 

The ship carried 50 or more small calibre guns firing lead shot with an iron core. They were intended for anti-personnel use at close range, with tactics designed to injure or kill the enemy ships’ personnel, followed by boarding to capture the vessel. Led by Lund University Professor Nicolo Dell’Unto, the Lund University team recreated the guns from 3D models of the artifacts. (Watch video story detailing the artillery)

A Danish ‘floating castle’

Gribshunden was built near Rotterdam between 1483-84. King Hans of Denmark and Norway had taken possession of the ship by spring 1486. The high cost of building and equipping these ships meant Gribshunden probably absorbed about 8% of the Danish national budget in 1485. 

Hans utilized his flagship differently from other monarchs; he personally sailed on it frequently, using it not for exploration, but to solidify his grasp on his kingdom. It was his floating castle, enabling royal travel to Sweden and all around the Danish realm including Gotland and especially Norway. The king used this vessel in ways similar to a terrestrial royal fortification. This included several soft power functions: economic, diplomatic, social, cultural, and administrative. Underpinning all of these was the obvious hard power of the ship’s martial purpose embodied by the guns and other weapons carried aboard.

Evidence of explosion

Gribshunden served the crown for a decade before sinking while the king was en route from Copenhagen to a political summit in Sweden, where he expected to unify the entire Nordic region in a new Kalmar Union. Historical documents including eyewitness accounts relate that while Hans was ashore in Ronneby, an explosion and fire claimed the ship while it was anchored off the town. 

Among the 22-lead artillery shots from Gribshunden, several are flattened on one or two sides. This may be a result of the explosion that sank the vessel. Shot stored in the hold near the gunpowder ricocheted inside the ship.

No Nordic expansion into North America

So, given the existence of these warships, why didn’t Denmark compete in expanding to the Americas? Denmark and Norway shared the long Viking and medieval Nordic history of exploration and settlement in the west, with colonies in Iceland and Greenland, and settlements in North America. Coupled with adoption of this new enabling technology, Hans might have successfully competed with the Iberian rulers in global exploration and expansion to the Americas. 

However, Hans’ primary concern was consolidating rule over the Baltic region. In pursuit of that goal, Hans himself sailed on Gribshunden into the Atlantic on several royal visits, and to Kalmar on the ship’s final voyage.

One reason for Denmark’s inattention to the Americas might have been a 1493 papal bull signed by Pope Alexander VI. This granted Spain rights to the Americas, and a treaty between Spain and Portugal ceded the Indian Ocean to the latter. Prior to the Reformation, the threat of excommunication for ignoring the papal ‘Inter Caetera’ was very real.

(VIDEO MATERIAL IS AVAILABLE UPON REQUEST, AS WELL AS MORE IMAGES THAN THOSE ATTACHED)

Summary of the publication:

- Presents the artillery of a well-preserved late medieval Danish-Norwegian carvel warship, Gribshunden

- Of its original 50 or more guns, elements of 11 have been recovered and digitally recreated, and more remain on the wreck

- Provides insights into the development of shipboard artillery in the late 15th century

More about the study:

The study was written by archaeologists Brendan Foley and Martin Hansson, with English medieval artillery expert Kay Douglas Smith. The project is conducted in collaboration with Blekinge Museum, Vikingeskibsmueet, and Ronneby municipality. The research was funded by grants from the Swedish Research Council (Vetenskapsrådet), Crafoordska Stifltelsen, Huckleberry Foundation (USA), and with support from Blekinge Museum and the Lund University Department of Archaeology and Ancient History.

The Gribshunden artillery artifacts are exhibited and curated at the Blekinge Museum facility in Rosenholm, with select artifacts on temporary display in Kallvattenkuren in Ronneby, and in Museet for Søfart in Helsingør, Denmark. Plans are underway to create a dedicated Gribshunden museum in Ronneby, where the artillery and other objects from the wreck may ultimately find a permanent home.

 

 

AI model maps building emissions to support fairer climate policies



Open-source approach uses publicly available data and machine learning to identify carbon hotspots and guide targeted urban decarbonisation.




National University of Singapore College of Design and Engineering

Department of Architecture PhD student and Lead Author Winston Yap (left) with Asst Prof Filip Biljecki (right) who led the research. 

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Department of Architecture PhD student and Lead Author Winston Yap (left) with Asst Prof Filip Biljecki (right) who led the research.

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Credit: College of Design and Engineering at NUS






An open-source artificial intelligence model to accurately map the carbon emissions of buildings across multiple cities could become a powerful new tool to help policymakers plan targeted and equitable decarbonisation strategies.

The model, developed by researchers at the College of Design and Engineering (CDE) at the National University of Singapore (NUS), offers city planners a detailed picture of how building carbon emissions are distributed and what drives them, with a view to helping authorities design smarter, fairer strategies to cut emissions.

The model is the result of research led by Assistant Professor Filip Biljecki from the Department of Architecture at CDE. The team’s findings were published on 15 August 2025 in the journal Nature Sustainability.

“Our model estimates operational carbon emissions of individual buildings at the scale of entire cities,” said Department of Architecture PhD student Winston Yap, Lead Author of the study.

“Unlike previous approaches that rely on proprietary data, our open approach is designed to be transferable across cities, including those with different data availability conditions.”

Applied to data mapping over half a million buildings in five cities - Singapore, Melbourne, New York City (Manhattan), Seattle and Washington DC - the researchers say their model explained up to 78 per cent of the variation in emissions. The results revealed significant differences in how emissions are distributed within cities and identified key factors that influence building energy use, including urban form, planning history, and income levels.

“Building emissions are not just about size or density, they’re deeply shaped by the unique context of each city, from its planning legacy to climate and economic conditions,” said Asst Prof Biljecki. “By using only open data, we’ve built a flexible framework that cities around the world can use to better understand their carbon footprint and plan more effective responses.”

One of the key insights from the study is the complex relationship between building density and carbon emissions. While taller buildings tend to be more energy-efficient per unit area due to economies of scale, dense urban cores may also experience higher cooling demands due to urban heat island effects. Suburban areas, typically associated with detached low-rise buildings, were found to be significant contributors to total emissions, sometimes rivalling those of city centres.

The research also uncovered stark inequalities. In most cities studied, wealthier neighbourhoods were found to have disproportionately high per capita emissions. In Manhattan, for example, more than half of total building emissions were attributed to just a handful of large buildings.

“Uniform carbon pricing or blanket regulations risk placing an unfair burden on lower-income communities that may already be struggling with older, less efficient infrastructure,” said Asst Prof Biljecki. “Our findings highlight the need for place-based strategies that take both emissions intensity and socioeconomic vulnerability into account.”

The framework integrates diverse data sources including satellite imagery, street view photos, population maps, road networks, and local climate data using graph neural networks, a form of deep learning that captures spatial relationships between urban elements.

By making their approach entirely open, the researchers say they want to support global efforts to reduce emissions from the built environment and to help cities meet their climate targets.

“This work demonstrates the potential of open science and AI to accelerate urban sustainability,” said Asst Prof Biljecki. “It’s not just about understanding where emissions come from, but also ensuring that climate action is both effective and fair.”

 

Encoding of blink information via wireless contact lens for eye-machine interaction



Science China Press
Design of eye-machine interaction system 

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(a) Left: encoding of blink information, the schematic indicates that the brain generates specific commands and stimulates the eyes to blink accordingly when a specific situation is encountered. Centre: EMI lens. Right: decoding the blink information for machine interface, healthcare, and AR/VR. (b) I, The exploded structure diagram of the blink-recognizable EMI lens, II, digital photographs of the EMI lens in different orientations. (c) The internal circuit of the EMI lens and the reading circuit of the frequency signal. (d) The encoding and decoding process of blink information. The capacitance of the sensor in designed EMI lens changes when the eyes switch between different states (eyes open, squinting, and eyes closed), and then covert to frequency, which is recorded by the external coil and transmitted to the electrical circles for signal process, finally decoding for the drone control application.

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Credit: ©Science China Press






EMI has emerged as a promising paradigm for human-computer interaction, yet its development has been hindered by several technical challenges including limited signal accuracy, poor wearability, and visual interference. To address these issues, research team led by Prof. Guozhen Shen (Beijing Institute of Technology) and Prof. Zhiyong Fan (Hong Kong University of Science and Technology) has developed an innovative flexible electronic solution - a smart contact lens integrated with an LC resonant circuit that achieves both high sensitivity and excellent biocompatibility for wireless EMI applications.

Unlike brain-computer interfaces (BCI) based on electroencephalography which needs complex algorithms and electrical circuits, EMI accomplishes the command based on consciousness information generated from the brain via simple ocular movements, the accuracy of which is much higher than that of BCI. Ocular movements primarily include blinks and eye rotation. Existing devices for monitoring ocular movements mainly rely on charge coupled devices (CCD) cameras or metal coil-embedded contact lenses, but the former requires complex external hardware, while the latter affects wearing comfort and field of vision due to rigid components. Compared to eye rotation, blinking offers significant advantages: its visibility, stability, and natural pressure characteristics (the eyelid exerts approximately 30 mmHg of pressure on the cornea during blinking) make it easier to capture with highly sensitive sensors. Additionally, parameters such as blink count, duration, and left/right eye can be encoded to generate diverse commands. Therefore, blink-based EMI systems demonstrate substantial application potential.

The research team designed an EMI system using a multilayer-structured flexible smart contact lens (EMI lens) as the core component. The EMI lens employs flexible materials as the substrate, integrating Ti3C2Tx MXene electrode layers, a honeycomb-structured microporous dielectric layer, and an induction coil to form a complete LC resonant circuit. Pressure variations alter the spacing of the microstructured dielectric layer, thereby changing the capacitance value. This change is converted into measurable frequency signals (detectable by external vector network analyzers) through the LC resonant circuit, enabling wireless pressure monitoring.

Without compromising vision or wearing comfort, the EMI lens can sensitively detect corneal deformation caused by intraocular pressure (IOP) changes and eyelid pressure induced by blinking. The system features dual functional modes: within the normal IOP range (10-21 mmHg), signals are converted into real-time monitoring data; when specific pressure (~30 mmHg) is detected, algorithms translate blink signals into control commands.

In wearability tests, subjects showed no significant physiological rejection or discomfort, confirming the feasibility of practical EMI lens applications. Additionally, the human eye performs 10-20 unconscious blinks per minute, which constitute interference signals in EMI. The EMI lens-based system achieves precise recognition by analyzing blink duration and pressure amplitude, effectively distinguishing conscious from unconscious blinks, with good accuracy in practical tests.

The research team developed a blink-based control command encoding/decoding mechanism that maps different blinking behaviors to flight commands, experimentally validating the feasibility of controlling multidimensional drone movements through blinking. In vivo rabbit tests further confirmed the system's reliability, with normal physiological conditions observed post-experiment. These results fully demonstrate the practical value of the EMI lens-based system in medical monitoring and human-machine control.

Eye-machine interaction applications 

(a) Different application scenarios of the EMI lens include both health monitoring and eye-machine interaction. (b) Digital photograph of the EMI lens actually worn in the human eye. (c) Recognition of conscious and unconscious blinks and generation of drone control commands. (d) Panels I -IV represent the signal waveform graphs and drone flight trajectories when the drone rotates clockwise, counterclockwise, forward, and backward, respectively. In the signal waveform graphs, the purple, blue, green, and red curves indicate whether the model or rabbit blinks, the measured value of pressure, the capacitance of the mechanosensitive capacitor, and the resonance frequency of the EMI lens, respectively.

Credit

©Science China Press